Woven and knitted fabrics with improved properties and core spun yarns for producing the same

ABSTRACT

A woven or knitted fabric with improved properties is formed of core spun yarns each including (i) a core draw textured yarn (DTY) consisting of a core material of polyethylene terephthalate (PET); and (ii) a wrapper of cotton staple fibers, polyester staple fibers, rayon staple fibers, modal staple fibers, fire retardant staple fibers or a blend thereof. The fabric may be produced by ring spun, open-end or vortex. The fabric may be produced by different weaving and knitting methods. Regular yarns are mixed in the fabric.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation-In-Part Application of U.S.patent application Ser. No. 13/655,422 filed on Oct. 18, 2012, whichclaims priority of U.S. provisional patent application No. 61/550,464filed on Oct. 24, 2011, the entire content of which is herebyincorporated by reference.

FIELD OF THE TECHNOLOGY

The present application relates to woven and knitted fabrics withimproved tensile and tear strength properties, improved abrasionresistance properties, and natural and permanent wrinkle resistanceproperties. The present application also relates to core spun yarns forproducing the woven and knitted fabrics with the improved properties.

BACKGROUND

In order to increase tensile and tear strength, heavier fabrics withthicker and heavier yarns are usually utilized. These fabrics arethicker and heavier to meet the strength requirements. As a result,these fabrics tend to cause much discomfort to the wearer of theapparel, particularly in summer months.

The wrinkle resistant properties of a fabric are normally achieved withthe application of resins containing, among other chemicals,formaldehyde and then curing by heat. However, the rating of wrinkleresistance will deteriorate as the apparel is repeatedly laundered.Furthermore, formaldehyde has been classified by the National Institutesof Health as being a carcinogen.

In order to increase abrasion resistance, heavier fabrics with thickerand heavier yarns are also utilized. These fabrics are thicker andheavier to meet the requirements. Again, as a result, these fabrics tendto cause much discomfort to the wearer of the apparel, particularly inthe summer months.

Furthermore, the cost of these thicker and heavier fabrics isnecessarily increased due to the use of more materials.

Hence, there is a need to produce woven and knitted fabrics withimproved properties.

The above description of the background is provided to aid inunderstanding woven/knitted fabrics and core spun yarns, but is notadmitted to describe or constitute pertinent prior art to thewoven/knitted fabrics and core spun yarns disclosed in the presentapplication, or consider any cited documents as material to thepatentability of the claims of the present application.

SUMMARY

According to one aspect, there is provided a core spun yarn including acore yarn and a wrapper wrapping around the core yarn. The core yarnincludes a core draw textured yarn (DTY) consisting of a core materialof polyethylene terephthalate (PET). The wrapper includes a wrapmaterial selected from the group consisting of 100% cotton staplefibers, polyester cotton blended staple fibers, 100% polyester staplefibers, 100% rayon staple fibers, 100% modal staple fibers, 100% fireretardant staple fibers, polyester rayon blended staple fibers andcotton rayon blended staple fibers and blends thereof.

In one embodiment, a diameter of the DTY is in a range of 20-50D.

According to another aspect, there is provided a fabric made of a corespun yarn having a core yarn and a wrapper wrapping around the coreyarn. The core yarn includes a core draw textured yarn (DTY) consistingof a core material of polyethylene terephthalate (PET). The wrapperincludes a wrap material selected from the group consisting of 100%cotton staple fibers, polyester cotton blended staple fibers, 100%polyester staple fibers, 100% rayon staple fibers, 100% modal staplefibers, 100% fire retardant staple fibers, polyester rayon blendedstaple fibers and cotton rayon blended staple fibers and blends thereof.

In one embodiment, F count of yarn of the fabric is in a range of24-144.

In one embodiment, the fabric may further include a non-core yarn. Thefabric may be formed with a mixture of the core spun yarns and thenon-core yarns.

In one embodiment, the ratio of core spun yarns to non-core yarns can beone core spun yarn to one or more non-core yarns.

In one embodiment, the mix of core spun yarns to non-core yarns is onecore spun yarn interlaced with one non-core yarn of similar yarn countand blend, and for every inch 64 core spun yarns and 64 non-core yarnsare employed as warp yarns, 30 core spun yarns and 30 non-core yarns areemployed as weft yarns.

In one embodiment, the fabric may have a weaving configuration selectedfrom the group consisting of poplin weave, poplin rip stop weave, lefthand twill 2:1 weave, left hand twill 2:2 weave, left hand twill 3:1weave, right hand twill 2:1 weave, right hand twill 2:2 weave, righthand twill 3:1 weave, left hand sateen 4:1 weave, right hand sateen 4:1weave, canvas 1:1 weave, canvas 2:2 weave, oxford 2:2 double ply weave,cavalry weave, dobby weave, jacquard weave, corduroy weave and flannelweave.

In one embodiment, the fabric may have a weft knit configurationselected from the group consisting of jersey, rib 1×1, rib 2×1, rib 2×2,rib 3×3, single pique, double pique, fleece, French terry, interlock,feeder stripe, engineering stripe, dobby and jacquard.

In one embodiment, the fabric may have a warp knit configurationselected from the group consisting of tricot and rachel.

In one embodiment, the fabric can be produced by core spun yarns formedby a core sheath selected from the group consisting of ring spun coresheath, open-end core sheath or vortex core sheath.

According to yet another aspect, there is provided an article of apparelmade of the fabric of the present application. The article of apparelmay be selected from T shirts, polo shirts, knit shirts, knit shorts,knit pants, knit jackets, woven shirts, woven pants, woven jackets,denim jeans, denim shirts, denim jackets, chambray shirts, yarn dyedshirts, yarn dyed shorts, yarn dyed pants, bed sheets and pillow cases.

In one embodiment, the core spun yarn is produced by wrapping the wrapmaterial around the core material utilizing a ring spin core spunmachine. The wrap material includes polyester staple fiber of 1.5 D with38 mm staple length blended with cotton fiber in a ratio of 74.1%poly/25.9% cotton. The weaving configuration is 3:1 left hand twill andthe woven fabric construction is 128 yarns of Ne 20 s/l for warp yarnand 60 yarns of Ne 20 s/l for weft yarn.

In one embodiment, the fabric is sewn into a pair of pants, and thefabric is dyed and then finished.

Although the woven/knitted fabrics and core spun yarns disclosed in thepresent application are shown and described with respect to certainembodiments, it is obvious that equivalents and modifications will occurto others skilled in the art upon the reading and understanding of thespecification. The present application includes all such equivalents andmodifications, and is limited only by the scope of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Specific embodiments of the woven/knitted fabrics and core spun yarnsdisclosed in the present application will now be described by way ofexample with reference to the accompanying drawings wherein:

FIG. 1 is a cross sectional view of a core spun yarn according to anembodiment of the present application.

FIG. 2 is a perspective view of a core spun yarn with core and sheathyarns according to another embodiment of the present application.

FIG. 3 is a schematic diagram showing a weaving configuration accordingto one embodiment of the present application.

FIG. 4 is a schematic diagram showing a weaving configuration accordingto another embodiment of the present application.

DETAILED DESCRIPTION

Reference will now be made in detail to a preferred embodiment of thewoven/knitted fabrics and core spun yarns disclosed in the presentapplication, examples of which are also provided in the followingdescription. Exemplary embodiments of the woven/knitted fabrics and corespun yarns disclosed in the present application are described in detail,although it will be apparent to those skilled in the relevant art thatsome features that are not particularly important to an understanding ofthe woven/knitted fabrics and core spun yarns may not be shown for thesake of clarity.

Furthermore, it should be understood that the woven/knitted fabrics andcore spun yarns disclosed in the present application is not limited tothe precise embodiments described below and that various changes andmodifications thereof may be effected by one skilled in the art withoutdeparting from the spirit or scope of the appended claims. For example,elements and/or features of different illustrative embodiments may becombined with each other and/or substituted for each other within thescope of this disclosure and appended claims.

As used herein, the term “core yarn” means the internal core member of ayarn, which is normally formed by core spinning. And, as used herein,the term “filament yarn” means a yarn composed of one or more filamentsthat extend substantially along the entire length of the yarn.

FIG. 1 is a cross sectional view of a core spun yarn 10 according to anembodiment of the present application. The core spun yarn 10 may includea core yarn 11 and a wrapper 12.

The core yarn 11 may include a core material such as polyester filamentyarn, mechanical stretch polyester filament yarn, fire retardantpolyester filament yarn, spandex filament yarn, high strength polyesterfilament yarn, nylon filament yarn, mechanical stretch nylon filamentyarn, kevlar filament yarn, polypropylene filament yarn or a combinationthereof. The filament yarn may include one or more filaments 111.

Furthermore, according to an embodiment, the core yarn is a drawtextured yarn (DTY) having a core material of polyethylene terephthalate(PET). DTY is a fully draw, fully oriented polyester multifilament yarnwith soft crimp, high bulk and texture with cotton feel and very highdurability and retention properties. DTY is suitable for fabric end useslike outer/inner garments, skin-clinging garments, furnishings,upholstery, etc. This is a replacement of cotton and cotton blend yarnswith very low moisture content.

In the embodiment, DTY has a core material of polyethylene terephthalate(PET), which is a thermoplastic polymer resin of the polyester familyand is used in synthetic fibers.

The selection of core material is based on the desired characteristic ofthe yarn. For example, if a fire retardant fabric is desired, then afire retardant polyester filament yarn can be selected. If a highstrength fabric is desired, then a high strength polyester filament yarncan be selected. If a fire retardant and high strength fabric isdesired, then a combination of fire retardant polyester filament yarnand high strength polyester filament yarn can be selected.

The wrapper 12 can be wrapping around the core yarn 11. The wrapper 12may include a wrap material such as staple fibers 121. The staple fibers121 can be 100% cotton staple fibers, polyester cotton blended staplefibers, 100% polyester staple fibers, 100% rayon staple fibers, 100%modal staple fibers, 100% fire retardant staple fibers, polyester rayonblended staple fibers, cotton rayon blended staple fibers or a blendthereof.

FIG. 2 is a perspective view of a core spun yarn 20 according to anotherembodiment of the present application. This core spun yarn 20 mayinclude a core yarn 21 and a wrapper 22. In this embodiment, the coreyarn 21 may have filaments 211 that are closely packed together.

Similarly, the core yarn 21 may include a core material such aspolyester filament yarn, mechanical stretch polyester filament yarn,fire retardant polyester filament yarn, spandex filament yarn, highstrength polyester filament yarn, nylon filament yarn, mechanicalstretch nylon filament yarn, kevlar filament yarn, polypropylenefilament yarn or a combination thereof. The filament yarn may includeone or more filaments 211.

Again, the wrapper 22 can be wrapping around the core yarn 21. Thewrapper 22 may also include a wrap material such as staple fibers 221.The staple fibers 221 can be 100% cotton staple fibers, polyester cottonblended staple fibers, 100% polyester staple fibers, 100% rayon staplefibers, 100% modal staple fibers, 100% fire retardant staple fibers,polyester rayon blended staple fibers, cotton rayon blended staplefibers or a blend thereof.

The method of yarn production may include ring spun, open-end or vortex.Different spinning methods can produce different core sheaths such asring spun core sheath, open-end core sheath and vortex core sheath. Ringspun, open-end and vortex spinning machines can be used to produce theyarns. A particular spinning method would yield a particular yarncharacteristic leading to a particular fabric feature.

According to an embodiment, the core spun yarn including the core drawtextured yarn (DTY) consisting of a core material of polyethyleneterephthalate (PET) is produced by the following method. At first,polyethylene terephthalate (PET) polyester chips are prepared.

Polyethylene Terephthalate (PET) Polyester Chips

Material Data Test conditions Properties (Status) Test Data Unit HeatMelting point ≦248 ° C. Inherent viscosity 0.85 ± 0.02 dl/gCrystallinity <60 % Tinctorial value L ≧88.9 b ≦1.4 Others Ethanalcontent ≦1.0 ppm Dust content ≦30 ppm Water 0.01 % Diethylene glycol 0.9%

Process of Polyethylene Terephthalate Polyester Chip-Spinning

1. Drying Process

Primary technical requirements:

-   Water content of the chip upon drying: <35 ppm-   Inherent viscosity of the chip upon drying: <0.02-   Equipments: ROSIN drying machine, faux BM drying machine

Conditions:

-   1) Pre-crystallization temperature: between the glass temperature    and the melting point of the chip. Generally controlled within the    range of 160˜180 degree Celsius.-   2) Pre-crystallization time: 8˜30 minutes, adjusted according to    needs.-   3) Pre-crystallization air pressure during fluidized bed process:    −5˜0 (cmwg)-   4) Drying temperature: The higher the temperature, the better the    drying effect. However, drastically high temperature may affect the    inherent viscosity and color tone of the chip. The temperature is    controlled within the range of 160˜185 degree Celsius accordingly.-   5) Drying time: controlled within 4˜12(H) generally in order to make    the water content of the chip close the average water content.-   6) Dry air dew point: The lower the dew point, the better the drying    effect. Usually controlled within <−30 degrees Celsius.-   7) Dry air pressure: usually controlled within the range of 0.6˜3.3    kgf/cm²

2. Spinning Process

Primary technical requirements: Inherent viscosity of oil-free yarns

-   Equipments: Barmag from Germany and other domestically produced    equipment

Technical Conditions:

-   1) Sectional temperatures within screw extruder-   A: Feeding stage: melting point of the chip +(0˜20) degrees Celsius-   B. Compression, metering section temperature: +(10˜40) degrees    Celsius-   2) Pressure on gauge pin of the screw extruder: It must be ensured    that the output of the metering pump is kept constant and that    energy consumption is minimized. In general, the pressure is    controlled within 8˜12 mpa.-   3) Spin manifold temperature: the boiler is heated by means of    diphenyl steam so as to ensure the temperature does not decrease and    is kept within 285˜298 degrees Celsius.-   4) Component pressure: Usually within 12˜28 mpa-   5) Pump delivery and rotational speed:

pump delivery (g/min)=spin speed (m/min)*denier of product (dtex)*N/1000

rotational speed of metering pump (RPM)=pump delivery (g/min)/density ofmelt

(g/cm³)*pump property (cm³/r)*pump efficiency(%)

-   6) Air cooling-   (1) Air speed: excessively high or low air speed will cause uneven    rate of increase in fiber strands. Usually kept within 0.3˜0.7 m/s-   (2) Air temperature: to ensure the cooling duration of melt jet is    not excessively long and minimize the deviation in cooling duration    of each monofil. Usually kept within 20˜28 degrees Celsius.-   (3) Air humidity (relative humidity): usually kept within 60˜90(%)-   (4) Air pressure: usually kept within 450˜600 p.a.

3. Drawing Process:

Determined by product's quality (physical properties and dyeing),production costs and other factors.

In an embodiment, the ring spinning technology is used for producingcore-spun yarns. Core-spun spinning is a one of the innovative spinningmethods. The yarn is spun with a chemical filament as the core andnatural fibers as the wrapping fiber. Low-elastic Draw Textured Yarns(DTY) are used as the core and natural cotton fibers and polyesterstaple fibers are used as the wrap fibers. By way of addition of athread guide mechanism and tension control device onto the ring spinningframe, the core-spun spinning mechanism of a ring spinning frame issimilar to the conventional spinning mechanism. However, twisting andwinding parameters will have a significant effect on core-spun spinning.During twisting, the wrap yarns, which originally should be aligned inparallel with fibers, have to be inclined at a certain angle with theaxis. The strand discharged by the front roller contracts gradually andforms a twisting triangular space, within which the number external andinternal fiber migration, the relative position between a filament and astaple fiber strand at the front nipper jaws and other factors will havea significant effect on the resultant core-spun yarn.

Example

The motion state of fibers in the twisting triangular space is studiedby an example of a core-spun yarn of a combed cotton and polyesterblended yarn wrapping a DTY50D/24F filament. The following assumptionsare made prior to analysis:

-   (1) The filament is fed in the middle of the strand-   (2) The filament can tolerate sufficiently large tension-   (3) The filament is a rigid body

When the yarn is twisted in the Z direction, after the silver and corefilament is discharged from the front roller, the strands form atwisting triangular space upon twisting.

As the yarn is twisted, the component force exerted on the fibersgenerates centrifugal pressure. The pressure is maximum along the edgesof the twisting triangular space and minimum around the centre of theyarn axis. Therefore, the peripheral fibers will overcome the resistancebetween fiber strands and migrate inwards under the influence of thecentrifugal pressure. The fibers then become loose instead of strained.On the contrary, the fibers near the centre of the yarn axis migrateoutwards due to the squeezing action. Part of the fibers will migrate tothe vicinity of the filament, alter its direction of migration out ofthe resistance exerted by the filament, and eventually move to theposition above the filament. The movement renders the filamentsurrounded by strands of wrapping fibers. Moreover, a fiber strand canundergo multiple migrations within the twisting triangular space. As faras the arrangement of fibers in a yarn is concerned, the fibers do notexist in layers. The spiral line of the fibers in a yarn takes a shapeof a cone. This characteristic helps connect fibers in the yarn byexternal and internal winding, and simultaneously facilitate a tendencyto wrap the central filament as the fiber strands contract and form atwisting triangular space.

Addition of a thread guide mechanism and tension control device onto thering spinning frame for spinning core-spun staple or long fibers has asignificant effect on yarn production. By way of altering the height,and width of the twisting triangular space, and the relative positionbetween a filament and strand of staple fibers, the wrapping effect willbe significantly improved.

As deduced from the assumption, the filament exists as a rigid body thatonly gives rise to self-twisting twists but not winding twists. Underthese circumstances, the filament remains in the middle of the yarn andhence the wrapping effect is at its best. A core-spun yarn is thenformed.

However, when the fibers migrating toward the filament are insufficient,the strands will form a cylindrical yarn before the wrapping fibersenclose the filament. In this sense, the yarns can only be attachedspirally on the filament as it is winded. Only the warped wrap yarnscontribute to the wrapped twisting. The length of lay inevitably rendersthe filament exposed.

Factors Affecting the Wrapping Effect of a Core-Spun Yarn

As shown in the analysis above, the factors affecting the wrappingeffect of a core-spun yarn include the number of internal and externalmigration of fibers, the relative position between a continuous filamentand strands of short fibers at the front nipper jaws, and others.

The draw textured yarn of polyester filament (55 dtex/36F) produced byShenghong Group is selected as the core yarn. The properties include abreaking strength of 52.3CN/tex, an elongation at break of 27.4%, aYoung's modulus of 332cN/tex. Below shows a variety of choices of coreyarns, of which the core yarn in testing is 50D/36F.

Dimensions of core yarns Dimensions F count 20D 24F 30D 24F 36F 35D144F  40D 72F 144F  50D 36F 48F 72F 96F

Wrapping Fibers

The composition of wrapping fibers contains polyester and cotton in theratio of 63 to 35. Second-grade Tibetan lint cotton and polyester fiberswith 1.56 tex*38 mm are selected. The qualities of the semi-product ofyarn include a yarn unevenness rate of 18.9%, and a weight unevenness of0.97%

Under the conditions that the yarn spacing, tex count of wrapping fibersat break draft and dimensions of yarn are determined, the function ofcore-spun yarns is primarily dependent on number of twist, tension ofcore yarn and so on. The core-spun yarn tested is 20 S+50 D.

Applicable Yarn Count

Dimension of Core-Spun Yarns

yarn count Core yarn 20S 50D 32S 50D 40S 30D 50S 20D

The core spun yarns 10, 20 can be formed into a woven fabric by aweaving machine. The woven fabric may have a weaving configuration suchas Poplin weave, Poplin Rip stop weave (as shown in FIG. 3), left handTwill 2:1 weave, left hand Twill 2:2 weave, left hand Twill 3:1 weave,right hand Twill 2:1 weave, right hand Twill 2:2 weave, right hand Twill3:1 weave (as shown in FIG. 4), left hand Sateen 4:1 weave, right handSateen 4:1 weave, Canvas 1:1 weave, Canvas 2:2 weave, Oxford 2:2 doubleply weave, Cavalry weave, Dobby weave, Jacquard weave, Corduroy weave orFlannel weave.

The core spun yarns 10, 20 can also be formed into a knitted fabric by aknitting machine. A weft knit fabric may have a weft knit configurationsuch as Jersey, Rib 1×1, Rib 2×1, Rib 2×2, Rib 3×3, Single Pique, DoublePique, Fleece, French Terry, Interlock, Feeder Stripe, EngineeringStripe, Dobby or Jacquard. A warp knit fabric may have a warp knitconfiguration such as Tricot or Rachel.

The woven and knitted fabric may include 100% core spun yarns 10, 20.The woven and knitted fabric may also include regular yarns. Theproportion of core spun yarn to regular yarn may have different ratios.For example, the ratio of core spun yarn to regular yarn may be one corespun yarn to one or more regular yarns. The regular yarns can be in theform of non-core yarns or any other suitable spun yarns of simplyconstruction. The mixing of regular yarns with core spun yarns 10, 20 ofthe present application can reduce the manufacturing cost of the wovenand knitted fabric formed therefrom. The ratio of one core spun yarn 31,41 to one regular yarn 32, 42 in woven fabrics is illustrated in FIGS. 3and 4.

It is contemplated that the woven and knitted fabric of the presentapplication can be formed into various articles of apparel such as Tshirts, polo shirts, knit shirts, knit shorts, knit pants, knit jackets,woven shirts, woven pants, woven jackets, denim jeans, denim shirts,denim jackets, chambray shirts, yarn dyed shirts, yarn dyed shorts, yarndyed pants, bed sheets and pillow cases.

In the drawings and the above description, there has been set forth anembodiment of the patent application. It is appreciated that the choicesof core material, wrapping material, core spun spinning method,weaving/knitting method, core spun yarn to regular yarn ratio andapparel application are used in a generic and descriptive sense only andnot for the purposes of limitation.

Example

In one exemplary embodiment, the fabric includes a core spun yarnwherein the core material is a polyester filament yarn of approximately57 D overall in diameter, which is constituted by 48 strands of 1.2 Dfilaments. In this embodiment, the core spun yarn is produced bywrapping sheath fibers around the core material utilizing a ring spincore spun machine. The wrap material in this embodiment includespolyester staple fiber of 1.5 D with 38 mm staple length blended withcotton fiber in a ratio of 74.1% poly/25.9% cotton. In the presentembodiment the weaving method is 3:1 Left Hand Twill, and theconstruction of the woven fabric is 128 yarns of Ne 20 s/l for warp yarnand 60 yarns of Ne 20 s/l for weft yarn. In the present embodiment, theratio of core spun yarns to regular yarns is 1 core spun yarn interlacedwith 1 regular non-core spun yarn of similar yarn count and blend. Thus,for every inch 64 core spun yarns and 64 regular spun yarns are employedas warp yarns, and 30 core spun yarns and 30 non-core spun yarns areemployed as weft yarns. The fabric in the present embodiment is used tosew into a pair of pants. The fabric can be dyed and finished in anormal manner.

Demonstration of Improved Tear Strength Properties

To demonstrate the improved properties in tear strength of the fabric inthe present embodiment as compared to a conventional polyester andcotton blended fabric, tests of the fabrics were conducted according toa test method entitled “ASTM D1424˜2009, Standard Test Method forTearing Strength of Fabrics by Falling-Pendulum Type (Elmendorf)Apparatus”. In this test, a slit was precut at a center of a testspecimen held between two clamps and the specimen was torn through apredetermined distance. The resistance to tearing was in part factoredinto the scale reading of the instrument and was computed from thisreading and the pendulum capacity.

A fabric specimen of a core spun polyester and cotton fabric of thepresent embodiment was then tested. The construction of the fabrics andthe results are shown in Table 1.

TABLE 1 T/C Twill 6.9 oz core spun fabric test results - compared toIndustry Standards:- Major Retailer Test Report For Standard Fabric InThe Present Woven >7.0 Oz Embodiment Comparison Tearing Warp  4.0 lb 13.2 lb 3.3 times Weft  3.5 lb  9.1 lb 2.6 times Tensile Warp 60.0 lb336.9 lb 5.6 times Weft 50.0 lb 144.0 lb 2.8 times

Demonstration of Improved Tensile Strength Properties

To demonstrate the improved properties in tensile strength of the fabricin the present embodiment as compared to a conventional polyester andcotton blended fabric, tests of the fabrics were conducted according toa test method entitled “ASTM D5034-2009, Breaking Strength andElongation of Textile Fabrics (Grab Test)”. This test is described asfollows:

1. A 100-mm (4.0-in.) wide specimen was held by clamps of a tensiletesting machine and force was applied until the specimen breaks. Valuesof breaking force and elongation of the test specimen were obtained frommachine scales, dials, autographic recording charts, or a computerinterfaced with the testing machine.

2. This test method describes the procedures for carrying out fabricgrab tensile tests using two types of specimens and three alternativetypes of testing machines. For reporting, the following identificationsystem of specific specimen and machine combinations was used.

Type of Specimen:

-   G—Grab-   MG−Modified grab

Type of Tensile Testing Machine:

-   E—Constant-rate-of-extension (CRE)-   L—Constant-rate-of-load (CRL)-   T—Constant-rate-of-traverse (CRT)

Possible combinations can be identified as follows:

Type of Tester Constant-Rate- Constant-Rate- Constant-Rate- TestSpecimen of-Extension of-Load of-Traverse Grab G-E G-L G-T Modified GrabMG-E MG-L MG-T

For example, test method D 5034, G-E refers to grab test carried out ona constant rate-of-extension tensile testing machine.

These tests show that the tensile strength of the polyester and cottoncore spun fabric of the present embodiment is 2.8-5.6 times more thanthat of the conventional polyester and cotton blend woven fabric ofequal or greater weight. Also, the tearing strength of the polyester andcotton core spun fabric of the present embodiment is 2.6-3.3 times morethan that of the conventional polyester and cotton blend woven fabric ofequal or greater weight.

Demonstration of Improved Wrinkle Resistance Properties

To demonstrate the improved properties in wrinkle resistance of thefabric in the present embodiment as compared to a conventional polyesterand cotton blended fabric, tests of the fabrics were conducted accordingto a test method entitled “AATCC Test Method 124-2005: Appearance ofFabrics after Repeated Home Laundering”. In this test, flat fabricspecimens were subjected to standard home laundering practices. A choicewas provided for hand or machine washing, alternative machine washcycles and temperatures, and alternative drying procedures. Evaluationwas performed using a standard lighting and viewing area by rating theappearance of specimens in comparison with appropriate referencestandards.

A fabric specimen of a core spun polyester and cotton fabric of thepresent embodiment was then tested. The construction of these fabricsand the results are shown in Table 2.

TABLE 2 T/C Twill 6.9 oz core spun fabric test results - compared toIndustry Standards: Test Report for Natural and Permanent WrinkleResistant fabric in the present Major Retailer Standard embodimentRemark Wrinkle Resistance 3.5 minimun 4.0 Natural and (AATCC 124) (WithResin) (No Resin) Permanent Wrinkle Resistant

The test shows that the wrinkle resistance rating of the presentembodiment is rated at 4.0 without application of any resin.

Demonstration of Improved Abrasion Resistance Properties

To demonstrate the improved properties in abrasion resistance of thefabric in the present embodiment as compared to a conventional polyesterand cotton blended fabric, tests of the fabrics were conducted accordingto a test method entitled ASTM D4966˜1998(2007), Option 1, “AbrasionResistance of Textile Fabrics (Martindale Abrasion Test Method)”. Thistest is described as follows:

1. Abrasion resistance was measured by subjecting the specimen torubbing motion in the form of a geometric figure, i.e., a straight line,which becomes a gradually widening ellipse, until it formed anotherstraight line in the opposite direction and traced the same figure againunder known conditions of pressure and abrasive action. Resistance toabrasion was evaluated by various means which are described as follow:

2. Evaluation

2.1 Option 1—The end point is reached on a woven fabric when two or moreyarns have broken, or on a knitted fabric when a hole appears.

2.2 Option 2—The end point is reached when there is a change in shade orappearance that is sufficient to cause a customer to complain.

2.3 Changes of shade can arise from a variety of reasons, for example,loss of raised finish from a fabric or of boucle loops or effects fromfancy yarns. Different types of yarn or fiber can cause pronouncedchanges in shade or appearance. In this case, the end point is assessedagainst the AATCC gray scale for color change.

2.4 The end point is reached when the shade change is assessed as theAATCC gray scale rating of 3 or lower.

2.5 Option 3—Determine the mass loss as the difference between themasses before and after abrasion. This loss may be expressed as apercentage of the mass before abrasion.

The fabric specimen of a core spun polyester and cotton fabric of thepresent embodiment was then tested. The construction of these fabricsand the results are shown in Table 3.

TABLE 3 T/C Twill 6.9 oz core spun fabric test results - compared toIndustry Standards:- Test Report for Major Retailer fabric in thepresent Standard embodiment Comparison Abrasion Resistance 2.550 cyclesover 70,000 cycle >27 times (ASTM D4966) Martindale

This test shows that the abrasion resistance of the polyester and cottoncore spun yarn fabric of the present embodiment is 27 times greater thanthat of the conventional polyester and cotton blend yarn woven fabric ofequal or greater weight.

While the woven/knitted fabrics and core spun yarns disclosed in thepresent application have been shown and described with particularreferences to a number of preferred embodiments thereof, it should benoted that various other changes or modifications may be made withoutdeparting from the scope of the appending claims.

What is claimed is:
 1. A core spun yarn comprising: (a) a core drawtextured yarn (DTY) consisting of a core material of polyethyleneterephthalate (PET); and (b) a wrapper wrapping around the core drawtextured yarn and comprising a wrap material selected from the groupconsisting of 100% cotton staple fibers, polyester cotton blended staplefibers, 100% polyester staple fibers, 100% rayon staple fibers, 100%modal staple fibers, 100% fire retardant staple fibers, polyester rayonblended staple fibers and cotton rayon blended staple fibers and blendsthereof.
 2. The core spun yarn as claimed in claim 1, wherein a diameterof the core draw textured yarn is in a range of 20-50 D.
 3. The corespun yarn as claimed in claim 2, wherein the diameter of the core drawtextured yarn is 20 D, 30 D, 35 D, 40 D or 50 D.
 4. A fabric comprisingthe core spun yarn as claimed in claim
 2. 5. The fabric as claimed inclaim 4, wherein F count of yarn of the fabric is in a range of 24-144.6. The fabric as claimed in claim 4, wherein the F count of yarn of thefabric is 24, 36, 48, 72, 96 or
 144. 7. The fabric as claimed in claim6, further comprising a non-core yarn, wherein the fabric is formed witha mixture of the core spun yarns and the non-core yarns.
 8. The fabricas claimed in claim 7, wherein a ratio of core spun yarns to non-coreyarns is one core spun yarn to one or more non-core yarns.
 9. The fabricas claimed in claim 7, wherein the mix of core spun yarns to non-coreyarns is one core spun yarn interlaced with one non-core yarn of sameyarn count and blend, and for every inch 64 core spun yarns and 64non-core yarns are employed as warp yarns, 30 core spun yarns and 30non-core yarns are employed as weft yarns.
 10. The fabric as claimed inclaim 5, comprising a weaving configuration selected from the groupconsisting of poplin weave, poplin rip stop weave, left hand twill 2:1weave, left hand twill 2:2 weave, left hand twill 3:1 weave, right handtwill 2:1 weave, right hand twill 2:2 weave, right hand twill 3:1 weave,left hand sateen 4:1 weave, right hand sateen 4:1 weave, canvas 1:1weave, canvas 2:2 weave, oxford 2:2 double ply weave, cavalry weave,dobby weave, jacquard weave, corduroy weave and flannel weave.
 11. Thefabric as claimed in claim 5, comprising a weft knit configurationselected from the group consisting of jersey, rib 1×1, rib 2×1, rib 2×2,rib 3×3, single pique, double pique, fleece, French terry, interlock,feeder stripe, engineering stripe, dobby and jacquard.
 12. The fabric asclaimed in claim 5, comprising a warp knit configuration selected fromthe group consisting of tricot and rachel.
 13. The fabric as claimed inclaim 5, wherein the fabric is produced by core spun yarns formed by acore sheath selected from the group consisting of ring spun core sheath,open-end core sheath and vortex core sheath.
 14. The fabric as claimedin claim 5, wherein the core spun yarn is produced by wrapping the wrapmaterial around the core material utilizing a ring spin core spunmachine.
 15. The fabric as claimed in claim 5, wherein the wrap materialcomprises polyester staple fiber of 1.5 D with 38 mm staple lengthblended with cotton fiber in a ratio of 74.1% poly/25.9% cotton.
 16. Thefabric as claimed in claim 5, comprising a weaving configuration of 3:1left hand twill and a woven fabric construction of 128 yarns of Ne 20s/l for warp yarn and 60 yarns of Ne 20 s/l for weft yarn.
 17. Thefabric as claimed in claim 5, wherein the fabric is sewn into a pair ofpants, and the fabric is dyed and then finished.
 18. An article ofapparel made of the fabric of claim
 5. 19. The article of apparel asclaimed in claim 18, wherein the article of apparel is selected from thegroup consisting of T shirts, polo shirts, knit shirts, knit shorts,knit pants, knit jackets, woven shirts, woven pants, woven jackets,denim jeans, denim shirts, denim jackets, chambray shirts, yarn dyedshirts, yarn dyed shorts, yarn dyed pants, bed sheets and pillow cases.